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::To answer your last point first, I'd say your comments show good faith, and a helpful and entirely appropriate attempt to get to the core of the (potential) dispute.   
 
::To answer your last point first, I'd say your comments show good faith, and a helpful and entirely appropriate attempt to get to the core of the (potential) dispute.   
 
::On one level, we may just be talking past each other.  I say "delay" because excited molecules will eventually relax, and new photons (in a different spectrum) are emitted.  Your comments suggest that you mistakenly believe that all of the energy of a black body photon is permanently returned to the Earth as thermal energy just because it's absorbed by an atmospheric molecule.  But the molecules that are excited this way have much more of a tendency to shed the energy through re-radiation than mere black-body radiation.  These molecules shed energy through a couple of different mechanisms, including new photon emission directly radiated into space, as if the energy was never absorbed in the first place.  Other mechanisms are less direct, and therefore take longer; still others really do end up dumping the energy back into the Earth as thermal energy.  Thus, to fully describe the effect of the absorbtion of photons at a given quantum of energy, you need a graph over time that shows the expectation value of the fraction of that energy that ends up being radiated into space anyway.  It may be that a physical chemist's training is better suited to the task of calculating that curve from first principles, but, from my perspective as a physicist, I'd say that the curve needs to be measured empirically.  Worse, it needs to be calculated for each quantum of energy throughout the absorbtion spectrum, because the tendency of a molecule to want to relax through photon emission is a function of its quantum mechanical properties (and because the re-emitted photons are in a different spectrum, and, therefore, not likely to be absorbed by primary greenhouse molecules).  The shapes of these curves are the major unknown I'm pointing to. [[User:QBeam]]
 
::On one level, we may just be talking past each other.  I say "delay" because excited molecules will eventually relax, and new photons (in a different spectrum) are emitted.  Your comments suggest that you mistakenly believe that all of the energy of a black body photon is permanently returned to the Earth as thermal energy just because it's absorbed by an atmospheric molecule.  But the molecules that are excited this way have much more of a tendency to shed the energy through re-radiation than mere black-body radiation.  These molecules shed energy through a couple of different mechanisms, including new photon emission directly radiated into space, as if the energy was never absorbed in the first place.  Other mechanisms are less direct, and therefore take longer; still others really do end up dumping the energy back into the Earth as thermal energy.  Thus, to fully describe the effect of the absorbtion of photons at a given quantum of energy, you need a graph over time that shows the expectation value of the fraction of that energy that ends up being radiated into space anyway.  It may be that a physical chemist's training is better suited to the task of calculating that curve from first principles, but, from my perspective as a physicist, I'd say that the curve needs to be measured empirically.  Worse, it needs to be calculated for each quantum of energy throughout the absorbtion spectrum, because the tendency of a molecule to want to relax through photon emission is a function of its quantum mechanical properties (and because the re-emitted photons are in a different spectrum, and, therefore, not likely to be absorbed by primary greenhouse molecules).  The shapes of these curves are the major unknown I'm pointing to. [[User:QBeam]]
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::Now, regarding my third point, the logistical curve, let me try to reformulate.  There are a certain, relatively fixed number of ergs/year emitted by the Earth in CO2's absorbtion spectrum.  (Your point about the spectum being T dependent is correct, but of small effect, since T==300K and delta-T<~3.)  The maximum greenhouse effect would have every one of those ergs absorbed (and then a certain fraction of them would be re-emitted anyway in other spectra, and the rest "trapped").  Call that fraction, as a function of the amount of CO2, x(C).  For any incremental increase in CO2, delta-C, the number of ergs retained is proportional to (1-x(C)).  Logistical curves behave this way--logarithms do not.  In short, the horizontal asymptote of a logarithm is infinity, but the horizontal asymptote (and upper bound) on the greenhouse effect is finite.  [[User:QBeam]]
    
:*The problem is, you are assuming good faith.  Unfortunately on the Internet that is at the top of the charts for never happening.  QBeam was stringing together buzz words and silly science in the hope they would lend creditability to his/her post, a fact you just proved, HelpJazz.  --<font color="#1E90FF" face="Comic Sans MS">[[User:TK|şŷŝôρ-₮K]]</font><sup><font color="DC143C">[[User_Talk:TK|/Ṣρёаќǃ]]</font></sup> 01:01, 20 October 2007 (EDT)
 
:*The problem is, you are assuming good faith.  Unfortunately on the Internet that is at the top of the charts for never happening.  QBeam was stringing together buzz words and silly science in the hope they would lend creditability to his/her post, a fact you just proved, HelpJazz.  --<font color="#1E90FF" face="Comic Sans MS">[[User:TK|şŷŝôρ-₮K]]</font><sup><font color="DC143C">[[User_Talk:TK|/Ṣρёаќǃ]]</font></sup> 01:01, 20 October 2007 (EDT)
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